dropmarker {
  -moz-appearance: none;
  -moz-box-align: center;
  -moz-box-pack: center;
  list-style-image: url("chrome://global/skin/arrow/arrow-dn.gif");
}

dropmarker:not([disabled="true"]):hover,
dropmarker:not([disabled="true"]):active {
  list-style-image: url("chrome://global/skin/arrow/arrow-dn-hov.gif");
}

dropmarker[disabled="true"] {
  list-style-image: url("chrome://global/skin/arrow/arrow-dn-dis.gif");
}
